Kreyenborg GmbH announced March 14 that it has filed a patent infringement lawsuit against PSI-Polymer Systems Inc. and PSI’s continuous backflush screen changer, the CSC/BF.

Visitors to NPE2012 will get to see both versions in person. PSI officials say the company will display the screen changer at NPE2012, at Booth 5991. Kreyenborg will show its screen changer at Booth 7271.

Kreyenborg, based in Münster, Germany, claims the PSI screen changer violates its U.S. patent rights. Kreyenborg filed suit in U.S. District Court in Atlanta and issued a news release to announce the suit.

Firing back with its own news release, PSI-Polymer Systems questioned the timing of the suit, just before NPE.

“PSI feels that the most recent accusations by Kreyenborg are nothing more than a marketing ploy to damage PSI’s reputation in the industry, given its timing of just two weeks prior to NPE,” PSI President Glenn Woodcock said.

The continuous backflush screen changers are designed to handle contaminated, recycled material.

Kreyenborg officials said the company’s U.S. patent No. 7,419,592B2 covers features in Kreyenborg’s “75 percent filter” technology, where at least three of four filter screens always remain in production during screen change and screen cleaning/backflushing.

Kreyenborg’s news release says the company took legal action in Germany to stop PSI-Polymer Systems, and PSI agreed to stop the infringement on German the patents.

Now Kreyenborg is asking U.S, District Court to prohibit further U.S. sales of its CSC/BF products. The company also wants triple damages and lawyer fees.

PSI’s statement calls the lawsuit “baseless” and said the Conover, N.C., company “intends to defend itself vigorously against Kreyenborg’s groundless claims.”

“PSI is confident that its new patent-pending continuous backflush screen changer design does not infringe upon Kreyenborg’s U.S. patent or any other existing patent,” the company said. PSI’s pending U.S. patent covers a design with 37 separate claims.

The two designs are “significantly different,” PSI said.

Managing Director Jan-Udo Kreyenborg said the company has made continuous investments to develop the “75 percent filter.”

“Unfortunately, it may be tempting for third parties to copy Kreyenborg’s first-class technology, and when this occurs, we will not hesitate to take all necessary steps to protect Kreyenborg’s R&D investments and intellectual property,” he said.